Advanced Higher Engineering Science Revision

What type of cost is paying pension contributions?

• Direct

• Indirect

• On Cost

• Capital

Answer explanation

On-cost: Additional costs associated with an employee or project, over and above the direct costs, which may include employee benefits, payroll taxes, or overhead costs.

Direct cost: Expenses that are directly tied to producing a specific product or providing a particular service, such as materials, labor, and other costs that are directly tied to the production of a product or service.

Indirect cost: Expenses that are not directly tied to a specific product or service, but are necessary for the overall operation of the business, such as rent, utilities, salaries for administrative staff, office supplies, and equipment maintenance.

Capital cost: Expenses incurred for purchasing, building, or improving a long-term asset that will be used in a business over an extended period of time, such as the purchase of a building, land, or major equipment.

A single-phase line feeds a rural property.  The cable is 150m long and has a resistance of 0.682Ω per kilometre.  The resistive power consumption at the property is 12kW.  The single-phase voltage is 230V.  Calculate the efficiency of the line (correct to 2SF)

Answer explanation

Total Resistance = 0.682x0.15

= 0.1023 Ohms

Current = Power / Voltage

= 12000 / 230

= 52.2 A

Power Loss = I^2 R

= 52.2^2 x 0.1023

= 278.75 W

Power in = Power Out + Power Loss

= 12000 + 278.75

= 12278.75 W

Efficiency = Po / Pi

= 12000 / 12278.75

= 98%

At what stage of a project should you consider a sustainable end of life?

• Design

• Introduction

• Growth

• Maturity

• Decline

Answer explanation

The only way to make the end of life as sustainable as possible is to design this into the product right at the beginning of the the product's life. i.e. you cannot ensure that the parts are able to be removed easily for recycling if you do not design them that way!

Which of these statements are true (check as many as are true)

• A, D and G are on the critical path

• B, C, and H are on the critical path

• E and F are on the critical path

• G and H are on the critical path

Answer explanation

These are the activities are the ones without float and therefore must be on the critical path.

A MOSFET graph is shown. What is the IDS at the Q point of this MOSFET?

(To the nearest whole number)

• 5mA

• 4mA

• 3mA

• 2mA

Answer explanation

At the Q point VDS would be 5V - if we find where this voltage meets the load line, we can see that ID = 4mA at this point.

What is the equation for the Bending Moment of the beam in terms of x (from the LHS of the beam) when 4 < x < 7?

BM =

Answer explanation

RA = 30kN RB = 45kN

At this point the UDL can be simplified to a point load, 2m from the left hand side.

SO BM = 30x - 40 (UDL point load) (x-2) - 16(x-4)

BM = -26x + 144

What shape of wave form would you expect to see at Vout?

• Triangular Wave

• Square Wave

• Sine Wave

• Mexican Wave

What is the correct Second Moment of Area for this shape?

Answer explanation

Calculate the Upper Threshold for the Schmitt Trigger.

Correct to 3SF, no unit required

Answer explanation

Remember that to calculate the upper threshold the Op Amp must already be saturated positively and when the upper threshold is met, it will saturate to "zero" therefore the Vout at this point is the larger Op Amp output voltage and therefore the current is flowing from the output to A as shown in the diagram.

Calculate the value of R required to give a frequency of 1000Hz

(2 SF - no unit required)